/*
 * Copyright 2010-2020 Alfresco Software, Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.activiti.engine.impl.cmd;

import java.io.Serializable;
import java.util.Map;

import org.activiti.engine.ActivitiIllegalArgumentException;
import org.activiti.engine.delegate.event.ActivitiEventType;
import org.activiti.engine.delegate.event.impl.ActivitiEventBuilder;
import org.activiti.engine.impl.interceptor.Command;
import org.activiti.engine.impl.interceptor.CommandContext;
import org.activiti.engine.runtime.Job;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 */
public class ExecuteAsyncJobCmd implements Command<Object>, Serializable {

	private static final long serialVersionUID = 1L;
	private static Logger log = LoggerFactory.getLogger(ExecuteAsyncJobCmd.class);
	protected String jobId;
	private Map<String, Object> cacheAttr;

	public ExecuteAsyncJobCmd(String jobId, Map<String, Object> cacheAttr) {
		this.jobId = jobId;
		this.cacheAttr = cacheAttr;
	}

	public Object execute(CommandContext commandContext) {

		if (jobId == null) {
			throw new ActivitiIllegalArgumentException("jobId is null");
		}

		// We need to refetch the job, as it could have been deleted by another
		// concurrent job
		// For exampel: an embedded subprocess with a couple of async tasks and
		// a timer on the boundary of the subprocess
		// when the timer fires, all executions and thus also the jobs inside of
		// the embedded subprocess are destroyed.
		// However, the async task jobs could already have been fetched and put
		// in the queue.... while in reality they have been deleted.
		// A refetch is thus needed here to be sure that it exists for this
		// transaction.
		Job job = commandContext.getJobEntityManager().findById(jobId);
		if (job == null) {
			log.debug("Job does not exist anymore and will not be executed. It has most likely been deleted "
					+ "as part of another concurrent part of the process instance.");
			return null;
		}

		if (log.isDebugEnabled()) {
			log.debug("Executing async job {}", job.getId());
		}

		commandContext.addAttributes(cacheAttr);
		commandContext.getJobManager().execute(job);

		if (commandContext.getEventDispatcher().isEnabled()) {
			commandContext.getEventDispatcher().dispatchEvent(ActivitiEventBuilder.createEntityEvent(ActivitiEventType.JOB_EXECUTION_SUCCESS, job));
		}

		return null;
	}

}
